Novel cold pilger mill

Abstract

The invention relates to the technical field of metal pipe machining equipment, and discloses a novel cold pilger mill which comprises a main frame body, a driving unit, a primary rolling unit, a middle rolling unit and a forming rolling unit. The primary rolling unit, the middle rolling unit and the forming rolling unit are in transmission connection through a synchronous transmission unit so as to keep synchronous rotation; the middle rolling unit is movably arranged on the main frame body in the pipe conveying direction and comprises a rolling part and a linear driving part used for driving the rolling part to move in the conveying direction. The middle rolling unit is designed to move in the pipe conveying direction, the distance between the middle rolling station and the primary and forming stations can be flexibly adjusted according to technological parameters such as materials, wall thicknesses and springback characteristics of different pipes, so that a roller type curve and rolling force distribution can be better matched with the deformation rule of the materials, and the deformation accuracy of the materials is improved. And therefore, the defects of ellipse, out-of-tolerance diameter, uneven wall thickness and the like are overcome.

Description

Technical Field

[0001] This invention relates to the field of metal pipe processing equipment technology, and more specifically, to a novel cold rolling mill. Background Technology

[0002] A cold rolling mill is a mechanical device used to cold roll metal billets to produce high-precision tubes with high surface quality. A traditional multi-pass cold rolling mill typically includes a primary rolling unit, an intermediate rolling unit, and a forming rolling unit arranged sequentially. During operation, the tube is rolled multiple times through the primary rolling unit, intermediate rolling unit, and forming rolling unit to finally obtain the desired round tube.

[0003] However, while traditional cold rolling mills can meet basic tube production needs, they still have certain shortcomings. For example, due to the differences in the springback characteristics, hardness, ductility, and other physical properties of different materials, and the fixed spacing between the rolling units of traditional cold rolling mills, it is difficult to precisely match the deformation and springback behavior of specific materials in terms of roll design and arrangement. This can easily lead to quality problems such as excessive ellipticity, unstable diameter, and uneven wall thickness in the formed round tubes. These problems are particularly pronounced when producing materials with high springback and very thin thickness.

[0004] Therefore, there is an urgent need for a cold rolling mill that can flexibly adjust the spacing between the rolling stations to adapt to different material properties. Summary of the Invention

[0005] The purpose of this invention is to provide a novel cold rolling mill to solve the aforementioned technical problems.

[0006] The present invention solves the above-mentioned technical problems through the following technical solutions: The present invention provides a novel cold rolling mill for tubes, comprising: a main frame, a drive unit, a primary rolling unit, an intermediate rolling unit, and a forming rolling unit; The drive unit is connected to the primary rolling unit, and the primary rolling unit, intermediate rolling unit and forming rolling unit are connected by a synchronous transmission unit to maintain synchronous rotation. The intermediate roller pressing unit is movably mounted on the main frame along the pipe conveying direction, and includes a roller pressing part and a linear drive part for driving the roller pressing part to move along the conveying direction. The synchronous transmission unit includes a first transmission wheel disposed on the roller pressing section, two second transmission wheels disposed on the primary roller pressing unit and the forming roller pressing unit respectively, two annular transmission components connected between the corresponding first transmission wheel and the second transmission wheel, and two tension adjustment mechanisms. The tension adjustment mechanism is connected to the corresponding annular transmission component and is used to adjust the tension of the corresponding annular transmission component when the roller pressing section moves, so as to adapt to the position change of the first transmission wheel.

[0007] Preferably, the annular transmission component is a synchronous belt, and the first and second transmission pulleys are synchronous belt pulleys adapted to the synchronous belt.

[0008] Preferably, the annular transmission component is a chain, and the first and second transmission wheels are sprockets adapted to the chain.

[0009] Preferably, the tension adjustment mechanism includes a movably disposed tension wheel, an adjustment drive assembly for driving the tension wheel to move, and a guide assembly; the adjustment drive assembly is connected to the tension wheel through the guide assembly to drive the tension wheel to move along the adjustment direction; the tension wheel is connected to a corresponding annular transmission component for transmission.

[0010] Preferably, the adjustment drive assembly includes a first servo motor and a first lead screw that is connected to the first servo motor for transmission; the guide assembly includes a slide rail fixedly mounted on the main frame and a slider slidably mounted on the slide rail, and the tension wheel is rotatably mounted on the slider; the first lead screw is threadedly connected to the slider.

[0011] Preferably, the rolling section includes a movable frame slidably disposed on the main frame, a rolling body and a lower support roller disposed parallel to the movable frame, and a roller gap adjusting member for adjusting the distance between the upper rolling body and the lower support roller; the linear drive section is connected to the movable frame for transmission.

[0012] Preferably, the roll gap adjusting component includes two adjusting rods disposed on the movable frame and two movable seats slidably disposed on the movable frame. The two adjusting rods are respectively threadedly connected to the two movable seats, and the two ends of the upper roller are respectively rotatably connected to the two movable seats.

[0013] Preferably, the linear drive unit includes a second servo motor and a second lead screw that cooperates with the second servo motor for transmission, and the second lead screw is threadedly connected to the moving frame.

[0014] Preferably, the tensioning wheel is located in the middle of the first transmission wheel and the corresponding second transmission wheel, facing upwards, and the three are arranged in an isosceles triangle.

[0015] Preferably, the drive unit is directly connected to the primary rolling unit; the primary rolling unit, the rolling section, and the forming rolling unit achieve synchronous rotation through a synchronous transmission unit.

[0016] The beneficial effects of this invention are as follows: This invention designs the intermediate rolling unit to be movable along the pipe conveying direction. It can flexibly adjust the distance between the intermediate rolling station and the primary and forming stations according to the process parameters such as the material, wall thickness, and springback characteristics of different pipes. This allows the roll profile curve and rolling force distribution to better match the deformation law of the material, thereby suppressing defects such as ellipticity, diameter deviation, and uneven wall thickness. It is especially suitable for the production of high-precision thin-walled pipes and high-springback material pipes. By setting up a synchronous transmission unit, the tension of the two annular transmission components is adjusted in real time and automatically by two independent tension adjustment mechanisms when the position of the intermediate roll pressing unit changes. This ensures that the transmission system is always in the optimal tension state, avoiding problems such as loosening, slippage or excessive tightness of the transmission belt caused by unit movement. It also ensures a strict synchronous rotation relationship between the primary, intermediate and forming roll pressing units, thereby guaranteeing the stability of the rolling process and the uniformity of tube material quality. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of a novel cold rolling mill for tubes according to the present invention; Figure 2 This is a front view of a novel cold rolling mill for tubes according to the present invention; Figure 3 This is a schematic diagram of the structure between the intermediate roll pressing unit and the synchronous transmission unit in a novel cold rolling mill of the present invention; Figure 4 This is a partial structural diagram of the main frame of a novel cold rolling mill according to the present invention.

[0018] In the diagram: 10, main frame; 20, drive unit; 30, primary roller pressing unit; 40, intermediate roller pressing unit; 401, moving frame; 402, upper roller pressing body; 403, lower support roller body; 404, second servo motor; 405, second lead screw; 406, adjusting rotating rod; 407, movable seat; 50, forming roller pressing unit; 60, synchronous transmission unit; 601, first transmission wheel; 602, second transmission wheel; 603, ring transmission component; 604, tensioning wheel; 605, first servo motor; 606, first lead screw; 607, slide rail; 608, slider; 70, tube. Detailed Implementation

[0019] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, features described in some examples may be combined in other examples.

[0020] Please refer to the following: Figures 1 to 4 A novel cold rolling mill for tubes includes a robust main frame 10, serving as the mounting base for all units. Along the tube conveying direction, a primary rolling unit 30, an intermediate rolling unit 40, and a forming rolling unit 50 are sequentially arranged on the main frame 10. A drive unit 20, typically employing a main motor and a reducer, is mounted on the main frame 10. The drive unit 20 is directly connected to the input shaft of the primary rolling unit 30 via a coupling or similar mechanism, providing rolling power. The primary rolling unit 30 performs initial rolling deformation on the tube 70, including an upper rolling roller and a lower forming support roller, and also includes an adjustment device for adjusting the distance between the upper rolling roller and the lower forming support roller. The forming rolling unit 50 similarly protects the upper rolling roller and the lower forming support roller, and also includes multiple side extrusion rollers to ultimately extrude the tube 70 into a circular tube 70.

[0021] The intermediate roll forming unit 40 is movably mounted on the main frame 10, enabling it to move precisely along the conveying direction of the tube 70. It includes a roll forming section that performs the rolling function and a linear drive section that drives the roll forming section to move.

[0022] The rolling section mainly includes a movable frame 401 slidably mounted on the main frame 10. An upper rolling body 402 and a lower support roller 403 are mounted vertically and parallel to each other on the movable frame 401. The upper rolling body 402 is connected to the movable frame 401 via a roll gap adjusting member. Specifically, the roll gap adjusting member may include two adjusting rods 406 vertically mounted on the movable frame 401 and two movable seats 407 connected to bearing seats of the upper rolling body 402. The movable seats 407 are threadedly engaged with the adjusting rods 406. By rotating the adjusting rods 406, the movable seats 407 and the upper rolling body 402 can be driven to move up and down, thereby precisely adjusting the roll gap (i.e., rolling clearance) between the upper rolling body 402 and the lower support roller 403 to accommodate different wall thicknesses of the tube 70.

[0023] A linear drive unit is used to drive the entire rolling section to move. In this embodiment, the mechanism includes a second servo motor 404 fixedly installed at the bottom of the main frame 10 and a second lead screw 405 that is connected to the output end of the second servo motor 404 for transmission, and the axis of the second lead screw 405 is parallel to the conveying direction of the tube 70. The bottom of the moving frame 401 is threadedly connected to the outer side of the second lead screw 405. When the second servo motor 404 is running, the rotation of the second lead screw 405 drives the moving frame 401 and the entire rolling section to move smoothly and accurately back and forth (i.e., along the conveying direction) along the guide rail on the main frame 10, thereby changing the position of the intermediate rolling station so that the position of the intermediate rolling unit 40 can be adjusted according to the physical properties of different materials, thereby performing a precise rolling operation on the tube 70 to ensure the accuracy of the final formed tube 70.

[0024] In order to achieve the strict synchronous rotation of the rolling parts of the above-mentioned primary rolling unit 30, the intermediate rolling unit 40, and the forming rolling unit 50, a unique synchronous transmission unit 60 is further designed. This unit mainly includes: a first transmission wheel 601, two second transmission wheels 602, two annular transmission members 603, and two tension adjustment mechanisms.

[0025] Among them, the first transmission wheel 601 is fixedly installed on the transmission shaft of the rolling part (this transmission shaft is specifically the rotating shaft of the upper rolling body 402). The two second transmission wheels 602 are respectively fixedly installed on the corresponding transmission shafts of the primary rolling unit 30 and the forming rolling unit 50. The annular transmission member 603 can be a high-strength synchronous belt or a roller chain. The first annular transmission member 603 is sleeved on the second transmission wheel 602 of the primary rolling unit 30 and the first transmission wheel 601 of the intermediate rolling unit 40; the second annular transmission member 603 is sleeved on the first transmission wheel 601 of the intermediate rolling unit 40 and the second transmission wheel 602 of the forming rolling unit 50. In this way, the power is transmitted from the shaft of the primary rolling unit 30 to the first transmission wheel 601 through the first annular transmission member 603, and then to the forming rolling unit 50 through the second annular transmission member 603, realizing the linkage of the three.

[0026] The two tension adjustment mechanisms are correspondingly connected to the two annular transmission members 603, and are mainly used to adaptively adjust the tension of the annular transmission members 603. Since the first transmission wheel 601 moves with the rolling part, the distance between it and the two fixed second transmission wheels 602 will change, resulting in a change in the tension of the two annular transmission members 603. For this reason, an independent tension adjustment mechanism is equipped for each annular transmission member 603.

[0027] The tension adjustment mechanism mainly includes a tension wheel 604, a guiding component, and an adjustment driving component. The rim of the tension wheel 604 is in transmission connection with the annular transmission member 603. If the annular transmission member 603 is a synchronous belt, the tension wheel 604 is a synchronous belt wheel adapted to this synchronous belt. If the annular transmission member 603 is a chain, the tension wheel 604 is a sprocket wheel adapted to this chain, which can be adjusted according to actual usage requirements. In this embodiment, a combination of a synchronous belt wheel and a synchronous belt is preferably used.

[0028] Preferably, the tension wheel 604 is arranged at a position slightly above the middle of the corresponding first transmission wheel 601 and the second transmission wheel 602, and the three are approximately in an isosceles triangle, which can provide the best wrap angle and tension adjustment effect.

[0029] The guiding component includes a slide rail 607 fixedly installed on the main frame body 10 and a slider 608 slidably assembled on the slide rail 607. The tension wheel 604 is rotatably installed on the slider 608 through a bearing.

[0030] An adjustment drive assembly is used to drive the slider 608 to move. In this embodiment, the adjustment drive assembly includes a first servo motor 605 and a first lead screw 606 that is connected to the output end of the first servo motor 605 for transmission, and the first lead screw 606 is threadedly connected to the slider 608. The first servo motor 605 operates according to the instructions of the control system, driving the first lead screw 606 to rotate, thereby causing the slider 608 and the tension wheel 604 to move along the slide rail 607.

[0031] When adjusting the position of the intermediate roller pressing unit 40, the intermediate roller pressing unit 40 is directly driven to move by the linear drive unit. If the intermediate roller pressing unit 40 moves away from the primary roller pressing unit 30, the first annular transmission member 603 is tightened, and its tension may be too high; at the same time, the second annular transmission member 603 may become loose. At this time, the control system can instruct two tension adjustment mechanisms to operate: the first tension adjustment mechanism drives its tension wheel 604 to move in the direction of loosening the transmission member to release the over-tight state of the first annular transmission member 603; the second tension adjustment mechanism drives its tension wheel 604 to move in the direction of tightening the annular transmission member 603 to compensate for the looseness of the second annular transmission member 603. Through this closed-loop adjustment, no matter what position the first transmission wheel 601 is in, the two annular transmission members 603 can maintain a preset and appropriate tension, ensuring smooth transmission without slippage, thereby ensuring the absolute synchronization of the rotation speed of the three roller pressing units.

[0032] The specific working process of the cold rolling mill provided by this invention is as follows: Preparation stage: Based on the material and specifications of the tube 70 to be rolled, the target roll gap (adjusting the roll gap adjustment component) and the target intermediate station position are set through the control system; Adjustment phase: The control system starts the second servo motor 404 of the linear drive unit to drive the intermediate roller pressing unit 40 to move to the target position. During this process, the position sensor set on the main frame 10 provides feedback on the real-time position. At the same time, the control system calculates the required tension compensation amount of the two annular transmission components 603 based on the position change of the first transmission wheel 601, and drives the first servo motors 605 of the two tension adjustment mechanisms to work together to adjust the position of the two tension wheels 604 in real time to ensure that the tension of the transmission belt is constant. Rolling stage: After adjustment, start drive unit 20. Power is transmitted through primary roll pressing unit 30 and synchronous transmission unit 60 to drive the three roll pressing units to rotate synchronously. Sheet-shaped tube 70 passes through primary, intermediate and forming roll pressing stations in sequence and is gradually rolled into the required round tube. Since the position of the intermediate station has been optimized, the flow and springback of the material can be effectively controlled, thereby obtaining high-precision products.

[0033] The cold rolling mill designed in this invention combines an adjustable intermediate roll pressing unit 40 with a synchronous transmission system with adaptive tensioning function. Without changing the existing synchronous transmission mechanism, it also solves the problem that existing cold rolling mills are difficult to adjust the processing mode according to the characteristics of incoming materials or process requirements, thereby improving the process adaptability and product precision of the cold rolling mill and enabling it to meet the processing needs of thinner and more resilient tubes 70.

[0034] The embodiments of the present invention have been described above, but the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention, all of which are within the protection scope of the present invention.

Claims

1. A novel cold rolling mill for tubes, characterized in that, include: Main frame, drive unit, primary roll pressing unit, intermediate roll pressing unit and forming roll pressing unit; The drive unit is connected to the primary rolling unit, and the primary rolling unit, intermediate rolling unit and forming rolling unit are connected by a synchronous transmission unit to maintain synchronous rotation. The intermediate roller pressing unit is movably mounted on the main frame along the pipe conveying direction, and includes a roller pressing part and a linear drive part for driving the roller pressing part to move along the conveying direction. The synchronous transmission unit includes a first transmission wheel disposed on the roller pressing section, two second transmission wheels disposed on the primary roller pressing unit and the forming roller pressing unit respectively, two annular transmission components connected between the corresponding first transmission wheel and the second transmission wheel, and two tension adjustment mechanisms. The tension adjustment mechanism is connected to the corresponding annular transmission component and is used to adjust the tension of the corresponding annular transmission component when the roller pressing section moves, so as to adapt to the position change of the first transmission wheel.

2. The novel cold rolling mill for tubes according to claim 1, characterized in that, The annular transmission component is a synchronous belt, and the first and second transmission wheels are synchronous belt pulleys adapted to the synchronous belt.

3. A novel cold rolling mill for tubes according to claim 1, characterized in that, The ring-shaped transmission component is a chain, and the first and second transmission wheels are sprockets adapted to the chain.

4. A novel cold rolling mill for tubes according to claim 1, characterized in that, The tension adjustment mechanism includes a movably mounted tension wheel, an adjustment drive assembly for driving the tension wheel to move, and a guide assembly; the adjustment drive assembly is connected to the tension wheel through the guide assembly to drive the tension wheel to move along the adjustment direction; the tension wheel is connected to a corresponding annular transmission component for transmission.

5. A novel cold rolling mill for tubes according to claim 4, characterized in that, The adjustment drive assembly includes a first servo motor and a first lead screw that is connected to the first servo motor for transmission; the guide assembly includes a slide rail fixedly mounted on the main frame and a slider slidably mounted on the slide rail, and the tension wheel is rotatably mounted on the slider; the first lead screw is threadedly connected to the slider.

6. A novel cold rolling mill for tubes according to claim 1, characterized in that, The roller pressing section includes a movable frame slidably mounted on the main frame, an upper roller pressing body and a lower support roller body arranged parallel to the movable frame, and a roller gap adjusting component for adjusting the distance between the upper roller pressing body and the lower support roller body; the linear drive section is connected to the movable frame for transmission.

7. A novel cold rolling mill for tubes according to claim 6, characterized in that, The roll gap adjusting component includes two adjusting rods mounted on a movable frame and two movable seats slidably mounted on the movable frame. The two adjusting rods are threadedly connected to the two movable seats respectively, and the two ends of the upper roller are rotatably connected to the two movable seats respectively.

8. A novel cold rolling mill for tubes according to claim 6, characterized in that, The linear drive unit includes a second servo motor and a second lead screw that works in conjunction with the second servo motor for transmission. The second lead screw is threadedly connected to the moving frame.

9. A novel cold rolling mill for tubes according to claim 4, characterized in that, The tensioning wheel is located in the middle of the first transmission wheel and the corresponding second transmission wheel, facing upwards, and the three are arranged in an isosceles triangle.

10. A novel cold rolling mill for tubes according to claim 1, characterized in that, The drive unit is directly connected to the primary roll pressing unit; the primary roll pressing unit, the roll pressing section and the forming roll pressing unit achieve synchronous rotation through a synchronous transmission unit.

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